Add dev server test data for an experimental run of Edge

This adds a test run for edge experimental on the testing sha
24278ab. It reuses the same json results as edge[stable]. The goal is
to make the webdriver tests more like reality (e.g. there should be 4
experimental browsers by default) and to allow us to remove the obsolete
experimentalAlignedExceptEdge flag (which is off in prod/staging but
still on for the dev server!)

util/populate_dev_data.go

@@ -89,6 +89,11 @@ func main() {
 	edge.ResultsURL = fmt.Sprintf(summaryURLFmtString, *localHost, staticRunSHA[:10], "edge[stable].json")
 	edge.Labels = []string{"edge", shared.StableLabel}
 
+	edgeExp := edge
+	edgeExp.BrowserVersion = "20"
+	edgeExp.ResultsURL = strings.Replace(edge.ResultsURL, "[stable]", "[experimental]", -1)
+	edgeExp.Labels = []string{"edge", shared.ExperimentalLabel}
+
 	firefox := chrome
 	firefox.BrowserName = "firefox"
 	firefox.BrowserVersion = "66"
@@ -115,6 +120,7 @@ func main() {
 		chrome,
 		chromeExp,
 		edge,
+		edgeExp,
 		firefox,
 		firefoxExp,
 		safari,

webdriver/label_test.go

@@ -15,13 +15,8 @@ import (
 
 func TestLabelParam_Results(t *testing.T) {
 	runWebdriverTest(t, func(t *testing.T, app AppServer, wd selenium.WebDriver) {
-		// Local static data only have 2 experimental browsers, and neither has aligned
-		// experimental runs.
-		if *staging {
-			testLabel(t, wd, app, "/", "experimental", "wpt-results", 4, false)
-		} else {
-			testLabel(t, wd, app, "/", "experimental", "wpt-results", 3, false)
-		}
+		aligned := false
+		testLabel(t, wd, app, "/", "experimental", "wpt-results", 4, aligned)
 	})
 
 }